1. Field of the Invention
The present invention relates to a display driver apparatus, and more particularly, to a display driver apparatus suitable for driving a liquid crystal display panel and an inversion driving method thereof.
2. Description of Related Art
A thin-film transistor liquid crystal display (TFT LCD) panel employs liquid crystals as the material for controlling the displaying effect, thus, in order to avoid the phenomenon of residual image caused by the liquid crystal polarization, the voltage polarity of a source signal must be periodically converted. The inversion driving method for the liquid crystal display panel comprises, for example, line inversion, column inversion, dot inversion, and the like. The ability for restraining flicker phenomenon is different for each inversion driving method. For example, the dot inversion uses the dot as a unit to perform the inversion driving, so it has better restraining effect to the flicker phenomenon.
Considering the cost, the conventional medium/small-sized TFT LCD generally employs the line inversion driving method. Take the conventional TFT LCD in FIG. 1 as an example, Rn, Gn, Bn in the liquid crystal display panel 101 represent three sub-pixels (or “dot”) for forming the nth pixel, corresponding to three primary colors red, green and blue respectively, wherein + represents positive polarity and − represents negative polarity. As shown in FIG. 1, the so-called line inversion means that, in the same frame, two adjacent gate lines (e.g., GL1 and GL2) employ opposite voltage polarities, and the polarity of the same gate line is also inverted between two successive frames.
Continue referring to FIGS. 1 and 2, a gate driver 102 is used to generate gate signals G1-G3, a source driver 106 is used to generate source signals S1-S3, and a common voltage generation unit 110 is used to generate a common voltage VCOM1. During an enable period T1 of the gate signal G1, each of the multiplexer units 103-105 respectively turns on the switches in the multiplexer units 103-105 in sequence according to switch signals SW1-SW6, and thereby, the source signal S1 is delivered to sub-pixels R0, G0, B0, R1, G1, B1 through the gate line GL1 in sequence, and the circumstance of the source signals S2 and S3 goes the same. As the common voltage at this time is a first voltage level V11, the voltage polarities of source signals S1-S3 delivered to the sub-pixels at this time are positive. After that, during the enable period T2 of a gate signal G2, the voltage polarities of source signals S1-S3 delivered by each multiplexer unit 103-105 are all negative. Thus, the conventional TFT LCD achieves displaying each frame by way of the line inversion driving.
However, the line inversion driving method of the conventional TFT LCD easily causes crosstalk and flicker phenomena in terms of the image quality. The flicker phenomenon caused by the line inversion is especially severe since the flicker phenomenon is generated with the line as a unit and is easy to be sensed by the user (which is even more severe in frame inversion display method). In other words, as the era of the high-pixel is coming, the image quality of the conventional TFT LCD is limited by the line inversion driving method, and also in frame inversion method, and cannot be further improved.